one. There are numerous ways to compensate for
oversensitivity. The program could average a few readings
to sort of gauge the solidity of an obstacle. Presumably,
an ephemeral obstacle will inconsistently reflect the IR
beams leading to a low average, while a solid obstacle
will consistently reflect the beams. Also, an array of
sensors would be able to provide more information, and
that may be one reason why the Mark III did indeed see
the obstacle – it is outfitted with two of the Sharp
rangefinders.

Closing Ceremonies

After our ephemeral obstacle, we had grand plans for a
third challenge based on our anticipation of receiving a
third type of sensor to test – the SRF05 from Devantech, an
ultrasonic rangefinder that we would equip to the Mark III.
Unfortunately, Devantech seems to be the Matt Damon to
our Jimmy Kimmel Live, and we just ran out of time
because the sensor didn’t arrive. We have heard nothing
but good things about Devantech from other tinkerers, but
we always seem to have bad luck. In any event, stay on the
lookout for a future project involving the SRF05. We still
tested the Scribbler with our rendition of an anti-echoic
obstacle meant to stymie an ultrasonic sensor, but both
bots had no problem avoiding that obstacle as easily as the
tissue box.

Our goal with the Sensor Olympics is fairly
straightforward: to gain an intuitive understanding of
the advantages and disadvantages of different types of
sensors. Sure, many sensors have nicely detailed
datasheets, but many of these stats about peak voltage
and power consumption don’t necessarily reveal
whether this sensor will work to get you through that
maze. Datasheets often don’t reveal how the sensor
will react to non-ideal conditions. This, however, is
an understandable limitation because it would be
foolish to expect concise datasheets to comprehensively
list all of the ways in which conditions can stray from
the ideal.